The family bought the meat from a local Walmart, which has been very cooperative with investigators and has turned over all of the bottom round steak that was on their shelves at the time, Tampa Police said Friday in a news release.

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It was not immediately clear how the steak that Ronnie Morales, 24, his girlfriend Jessica Rosado, 31, and her 7-year-old and 6-year-old daughters ate Monday night became contaminated with LSD. Test results provided Friday showed the presence of the hallucinogenic drug, police said.

Morales, 24, felt sick soon after eating dinner at 2744 Bel Aire Circle and called 911. But he felt so ill that Rosado, who was 9 months pregnant, drove him to St. Joseph's Hospital. That's when she felt sick and was rushed across the street to St. Joseph's Women's Hospital and was induced into labor, police said.

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Shortly thereafter, her daughters Elyana, 7, and Rayna, 6, began hallucinating and felt ill as well. Both girls and Morales were given tracheal intubations and were hospitalized, according to police.

They were released from the hospital in good condition two days later, on Wednesday.

Rosado, who gave birth to a boy, was released with her healthy son on Thursday, police said.

Authorities are still waiting for toxicology test results that were taken from the family members. Those are expected in the next three weeks, police said.

The meat was purchased at the Walmart at 1501 N. Dale Mabry Highway, and the Hillsborough County Medical Examiner's Office is testing all of the steak that the store turned over, police added.

"Like everyone else in the community, we are deeply disturbed about this situation and are taking it very seriously," Walmart spokesperson Dianna Gee said in a statement. "We want answers and we're committed to working with officials to get to the bottom of this."

Tampa Police detectives, the federal and Florida departments of agriculture and the Hillsborough County Health Department are investigating the LSD case. It appears to be an isolated incident, police said.